Tachyon

What Tachyon does

When a player hits another player, the hit travels from the proxy to the backend server, and the hit sound, hurt animation and knockback come back the same way. If the backend is far from the proxy, the attacker waits for that round trip before the hit feels like it landed.

Tachyon runs on the Velocity proxy and answers the attacker straight away. When a 1.21 or newer player hits another player, the proxy immediately sends the attacker:

• an attack sound at the attacker's position, of the same kind as the most recent attack sound near them;
• the hurt animation on the target;
• crit particles, when that most recent attack sound was a crit;
• the target's knockback, predicted from the knockback the server has given this attacker's earlier targets.

When the backend's own copies of those packets arrive, Tachyon drops them so the attacker does not see the hit twice. The backend still decides every hit. Damage, health and the knockback the server applies are unchanged.

Tachyon has a second, smaller part for Paper servers. See The Paper part.

When it steps in

• Only for players on Minecraft 1.21 or newer.
• Only for hits on other players. Hits on mobs are left alone.
• Only while the measured backend delay is at or above the threshold, 60 ms by default. Until a delay has been measured, Tachyon predicts.
• At most one prediction per target every 500 ms. Faster hits on the same target get no early feedback.

Tachyon measures the backend delay itself: the time between the proxy passing on a hit and the backend confirming the damage. This is the distance between the proxy and the backend, not the player's ping to the proxy. Measurements reset when the player changes server.

How knockback is predicted

Tachyon learns the knockback the server gives for this attacker's hits, separately for normal and sprint hits, from the velocity the server sends for each target. Very large velocities, such as explosions, are ignored. Until it has learned anything, it starts from a horizontal push of 0.4 and a vertical push of 0.36. Predicted knockback can be turned off; see Configuration.

Players can turn it off

Low ping mode is on for every player by default. A player can turn it off for themselves with /tachyon toggle. The choice lasts until they disconnect. See Commands and permissions.

The Paper part

The Paper part does nothing on its own. It gives Scala's minigame plugins, such as Duels and Bed Wars, a death delay for players with high ping: when such a player is eliminated, the game waits a few ticks before running its death handling. With the Paper part missing, those games run death handling straight away.

The delay is the player's ping as the Paper server measures it, used only when it is at or above 60 ms and capped at 300 ms, rounded up to whole ticks. Both numbers can be changed; see Configuration.

Requirements